congestion

Can the current Waverly Road/Highway 401 interchange handle a doubling of truck traffic to and from the St Marys Cement quarry?

Given that the Waterfront Trail shares the road in this section with the St Marys traffic plus the Highway 401 on/off traffic, can the Waterfront Trail be promoted as a safe and healthy recreational feature?

What mitigation measures will St Marys Cement propose to compensate for a large increase in heavy truck traffic which will affect commuters as well as recreational cyclists?

These are key questions raised by the Project Description for the Bowmanville Expansion Project.

The Project Description says that the aggregate will be moved “using existing road, rail and/or dock infrastructure”. But at the project’s Public Information Centre in Bowmanville on December 5, St Marys representative David Hanratty made clear that for the foreseeable future, the aggregate would go out by truck, not by ship or rail, primarily to customers on the east side of the Greater Toronto Area.

It is simply not cost-effective to load the aggregate onto ship, then load it again onto trucks enroute to construction projects, Hanratty said. Rail freight is now too expensive for a low-cost product like limestone aggregate, he added, in addition to the problem of needing to reload the material onto trucks for the “last mile” in any case.

So the 4,000,000 tonnes of limestone will all go out by truck. At 20 tonnes per truck, that would mean 200,000 truckloads per year, or 770 truckloads per day if the aggregate is hauled five days/week.

(Put another way, truck traffic in and out of St Marys is likely to more than double. While the current quarry extracts a similar amount of limestone as the underground expansion is projected to add, much of the current output is in the form of cement clinkers shipped out on the Capt. Henry Jackman. With a capacity of 30,000 tonnes, this ship can carry the equivalent of 1500 20-tonne truckloads each time it leaves port. But the aggregate shipments from the new underground mine will all go by truck.)

The timing of shipments to market will also affect traffic volume. If buyers are not prepared to stockpile aggregate through the winter, the hauling might be concentrated in the summer construction season – meaning the impact on the Waverly Road/Highway 401 interchange, and on the Waterfront Trail, could be especially heavy during summer.

The current Highway 401 on- and off-ramps in this location are far from ideal. On the south side, traffic coming off the eastbound 401 has to get past two stop signs before making it onto Waverly Road. The left turn onto Waverly Road will be more difficult when several hundred more trucks per day are heading north on Waverly.

Traffic getting off the eastbound 401 faces two stop signs before turning onto Waverly Road (red Xs), causing frequent back-ups along the off-ramp. Assuming most of the loads of aggregate from St Marys will go to the eastern GTA, the loaded trucks will travel north along Waverly Road (red arrow) to the 401 westbound ramp, making it more difficult for Bowmanville-bound traffic to turn onto Waverly Road from Energy Drive. The volume of traffic on the eastbound off-ramp will also be increased, due to empty aggregate trucks returning from GTA markets via the eastbound 401. (Image from Google Maps, December 13, 2016)

Perhaps this interchange can be re-engineered to handle the new traffic load. Is St Marys prepared to fund this reconstruction as part of its impact mitigation efforts?

As for the Waterfront Trail, the addition of several hundred more trucks per day to the section of shared Trail/roadway will make the Trail less attractive and less safe. Two changes might be made to mitigate this impact.

First, perhaps the Trail could be rerouted here to eliminate the sharing of congested roadway on Waverly Road and Energy Drive. Ironically, Google Maps currently shows an incorrect routing for the Waterfront Trail as shown below; could this route become reality in the future?

Although the Waterfront Trail is currently routed on Waverly Road and then along Energy Drive (as shown by the red arrows), Google Maps incorrectly shows a routing along the north edge of the St Marys property (the solid blue line). Could this route become reality in the future? (Image from maps.google.ca, December 13, 2016) click for larger view

Second, there is no safe and attractive route between the Waterfront Trail and most of the populated areas of Bowmanville. Cyclists from the north side of the 401 have two choices, both poor, for routes across the 401 to the Waterfront Trail (see Getting across the 401). One of these routes is Waverly Road, which will be more dangerous for cyclists if there is a major increase in truck traffic without an appropriate “complete streets” redesign.

Perhaps St Marys can mitigate the expansion project’s negative impact on the Waterfront Trail by funding a separate walking/cycling overpass or underpass at the 401. Such a routing would be a significant improvement to Bowmanville’s recreational trails, which currently offer no safe connection to the Waterfront Trail.

Top photo: Bumper-to-bumper traffic on off-ramp to Waverly Road from eastbound 401, December 13, 2016

Our transportation system is “magnificent, mysterious and maddening,” says the subtitle of Edward Humes’ new book. Open the cover and you’ll encounter more than a little “mayhem” too.

Is the North American economy a consumer economy or a transportation economy? The answer, of course, is “both”. Exponential growth in consumerism has gone hand in hand with exponential growth in transport, and Edward Humes’ new book provides an enlightening, entertaining, and often sobering look at several key aspects of our transportation systems.

Much of what we consume in North America is produced at least in part on other continents. Even as manufacturing jobs have been outsourced, transportation has been an area of continuing job growth – to the point where truck driving is the single most common job in a majority of US states.

Manufacturing jobs come and go, but the logistics field just keeps growing—32 percent growth even during the Great Recession, while all other fields grew by a collective average of 1 percent. Some say logistics is the new manufacturing. (Door to Door, Harper Collins 2016, Kindle Edition, locus 750)

With a focus on the operations of the Ports of Los Angeles and Long Beach, Humes shows how the standardized shipping container – the “can” in shipping industry parlance – has enabled the transfer of running shoes, iPhones and toasters from low-wage manufacturing complexes in China to consumers around the world. Since 1980, Humes writes, the global container fleet’s capacity has gone from 11 millions tons to 169 million tons – a fifteen-fold increase.

While some links in the supply chain have been “rationalized” in ways that lower costs (and eliminate many jobs), other trends work in opposite directions. The growth of online shopping, for example, has resulted in mid-size delivery trucks driving into suburban cul-de-sacs to drop off single parcels.

The rise of online shopping is exacerbating the goods-movement overload, because shipping one product at a time to homes requires many more trips than delivering the same amount of goods en masse to stores. In yet another door-to-door paradox, the phenomenon of next-day and same-day delivery, while personally efficient and seductively convenient for consumers, is grossly inefficient for the transportation system at large. (Door to Door, locus 695)

Humes devotes almost no attention in this book to passenger rail, passenger airlines, or freight rail beyond the short-line rail that connects the port of Los Angeles to major trucking terminals. He does, however, provide a good snapshot of the trucking industry in general and UPS in particular.

Among the most difficult challenges faced by UPS administrators and drivers is the unpredictable snarl of traffic on roads and streets used by trucks and passenger cars alike. This traffic is not only maddening but terribly violent. “Motor killings”, to use the 1920s terminology, or “traffic accidents”, to use the contemporary euphemism, “are the leading cause of death for Americans between the ages of one and thirty-nine. They rank in the top five killers for Americans sixty-five and under ….” (locus 1514)

In the US there are 35,000 traffic fatalities a year, or one death every fifteen minutes. Humes notes that these deaths seldom feature on major newscasts – and in his own journalistic way he sets out to humanize the scale of the tragedy.

Delving into the records for one representative day during the writing of the book, Humes finds there were at least 62 fatal collisions in 27 states on Friday, February 13, 2015. He gives at least a brief description of dozens of these tragedies: who was driving, where, at what time, and who was killed or seriously injured.

Other than in collisions where alcohol is involved, Humes notes, there are seldom serious legal sanctions against drivers, even when they strike down and kill pedestrians who have the right of way. In this sense our legal system simply reflects the physical design of the motor vehicle-dominated transport system.

Drawing on the work of Strong Towns founder Charles Marohn, Humes explains that roads are typically designed for higher speeds than the posted speed limits. While theoretically this is supposed to provide a margin of safety for a driver who drifts out of line, in practice it encourages nearly all drivers to routinely exceed speed limits. The quite predictable result is that there are more collisions, and more serious injuries or death per collision, than there would be if speeding were not promoted-by-design.

In the design of cars, meanwhile, great attention has been devoted to saving drivers from the consequences of their own errors. Seat belts and air bags have saved the lives of many vehicle occupants. Yet during the same decades that such safety features have become standard, the auto industry has relentlessly promoted vehicles that are more dangerous simply because they are bigger and heavier.

A study by University of California economist Michelle J. White found that

for every crash death avoided inside an SUV or light truck, there were 4.3 additional collisions that took the lives of car occupants, pedestrians, bicyclists, or motorcyclists. The supposedly safer SUVs were, in fact, “extremely deadly,” White concluded. (Door to Door, locus 1878)

Another University of California study found that “for every additional 1,000 pounds in a vehicle’s weight, it raises the probability of a death in any other vehicle in a collision by 47 percent.” (locus 1887)

Is there a solution to the intertwined problems of gridlock, traffic deaths, respiratory-disease causing emissions and greenhouse gas emissions? Humes takes an enthusiastic leap of faith here to sing the praises of the driverless – or self-driving, if you prefer – car.

“The car that travels on its own can remedy each and every major problem facing the transportation system of systems,” Humes boldly forecasts. Deadly collisions, carbon dioxide and particulate emissions, parking lots that take so much urban real estate, the perceived need to keep adding lanes of roadway at tremendous expense, and soul-killing commutes on congested roads – Humes says these will all be in the rear-view mirror once our auto fleets have been replaced by autonomous electric vehicles.

We’ll need to wait a generation for definitive judgment on his predictions, but Humes’ description of our present transportation system is eminently readable and thought-provoking.

What’s the cause of traffic congestion? Many people have a quick answer.

Traffic congestion? Obviously, there are too many cars.

Traffic congestion? That just means there isn’t enough road space.

Traffic congestion? It’s all those cyclists and streetcars getting in the way

With 45 years experience as a driver, 35 years as an everyday cyclist and seven years working in road construction, I’d like to think I’ve learned something about coping with – not to mention causing – congestion. But I’ve never had a day of formal education in traffic engineering or town planning.

So I opened Road Traffic Congestion: A Concise Guide with the hopes that it would offer methodical, realistic ways to look at both the causes of traffic congestion and its relief.

With its 400 pages of conciseness, this manual discusses the relationship between transportation technologies, the causes, characteristics and consequences of congestion, and the pros and cons of a wide range of relief strategies.

So is the problem too many cars, or not enough road? The experts open the book with a diplomatic dodge of this loaded question: “Congestion in transportation facilities – walkways, stairways, roads, busways, railways, etc. – happens when demand for their use exceeds their capacity.” (The mention of walkways and stairways notwithstanding, there is little attention given to foot-powered transportation, and with some notable exceptions in the closing chapters, the traffic discussed is car and truck traffic.)

Still in the opening chapters, Falcocchio and Levinson hint at another direction for investigation: “When growth in economic activities significantly outpaces the growth in transportation infrastructure investments, cities experience congestion to levels that make mobility difficult.” Would they make an evidence-backed argument, I wondered, that all the post-World War II investments in freeways, suburban arterials and parking lots have been disproportionately small?

But the book provides no real economic analysis, either of the comparative economics of different modes of transportation, nor the relationship of transportation infrastructure to the economy as a whole.

What the authors do provide is a systematic cataloguing of the ways in which traffic gets backed up on our roads, with examples from across the continent. To an outsider, their discussion illustrates both the strengths and the limitations of current traffic engineering practice.

Whether discussing backups associated with closely spaced traffic lights on a main arterial, or backups around a non-standard intersection with five spokes, the focus remains on finding ways to reduce the delay for cars and trucks. This is not to suggest that the authors are unaware of safety issues for cyclists and pedestrians; they are careful to note possible hazards for non-motorists and the need to minimize pedestrian/automobile conflict points.

But in most of the data they marshall from cities across North America, the factors which are measured and worked into formulas are data about vehicles: cars per lane per mile, total vehicle throughput, vehicle minutes of delay, average vehicle speed etc.

Just as significantly, the methods and formulas are applied to traffic moving on a single given street, as opposed to the sum of the traffic moving along a street and the traffic crossing it. For example, there are formulas for calculating how the addition of a signal light will impact traffic throughput on an arterial road – but how will this impact the travelers trying to cross that street? Clearly these are complex relationships, but if we focus only the rate of traffic flow on a given street, how can we know whether our traffic-enhancement strategies on that street are helpful or harmful to the circulation in the whole neighborhood or district?

It’s clear that lots of professional effort has gone into measuring and defining levels of congestion. So I was surprised to see the subjectivity at the heart of so much of the discussion. At what level of crowding does congestion begin? A National Cooperative Highway Research Program Report pegs congestion to “the travel time or delay in excess of that incurred under light or free-flow travel conditions.” Likewise, a 2011 Urban Mobility Report from the Texas Transportation Institute concludes that Chicago and Washington, DC drivers spend 70 hours extra hours each year in congested traffic, using as their baseline the time these same trips would take in “free-flow” conditions.

Falcocchio and Levinson, however, write that

in a large city it is not realistic to travel at free flow speed (or at the posted speed limit) in the peak hour. It is not logical, therefore to compare actual peak hour travel times to free-flow peak hour travel times when free-flow in the peak hour is a practical impossibility in a large city. (emphasis theirs)

While this strikes me intuitively as correct, I hoped they would offer a compelling argument to back up their position. That argument is missing from the book. A clue emerges, however, in their discussion of the flow and lack of flow on inner-city freeways.

By design, a freeway is one of the least complex traffic systems. Many variables that are present on city streets are absent on freeways; there are no traffic lights, no parking spaces, no direct access from driveways, traffic is divided into one-way streams, and only vehicles moving at roughly the same speed are allowed. It’s true that (for the time being) all drivers are human, and thus their reaction times vary and chaos can happen. But there are neat graphs for the typical relationships between density of traffic (in vehicles per lane per mile), vehicle speeds, and traffic throughput (in vehicles per lane per hour).

Traffic throughput on a freeway drops rapidly after density increases and speeds drop below the “critical speed” of 53 mph. This typically happens when density has increased to about 45 cars per lane per mile, with just under 100 feet between cars. Road Traffic Congestion, page 153.

These graphs show that up to a point, vehicle speeds slow modestly as traffic gets more dense, while total throughput still increases. When speeds drop below that point – the “critical speed” – the total throughput drops as well. On a typical freeway with design speed of 70 mph, this critical speed is 53 mph, and traffic tends to drop below this speed when density reaches 45 cars per lane per mile.

As the authors note, at this density there is an average of 97 ft between vehicles in each lane. So in pure spatial terms, the freeway is still closer to empty than to full. Yet it has already reached peak efficiency and any additional traffic will cause a drop in throughput – a drop that gets steeper with each increment of additional density.

In other words, a freeway needs to remain mostly empty to stay anywhere close to free-flow, if by free-flow we mean moving at close to its design speed. Not only must most of the space in each lane be unoccupied, but there are extra lanes required for emergency access; interchanges require lots of additional space; and because the freeway provides no direct access to the main city grid or to driveways, even more space is needed for service roads.

This, perhaps, is why it is practically impossible to achieve free-flow traffic at peak hour in a large American city: there simply isn’t the space to allow each and every commuter to drive simultaneously on almost-empty roadways.
And so we return to the question posed at the beginning: is congestion caused by too many cars, or not enough road? Cars will only move freely, Falcocchio and Levinson make clear, if there are fewer of them:

where added capacity is provided, its lasting effect on congestion relief (especially in metropolitan areas exceeding 2 million people) can only be realized by combining it with strategies that reduce the need to travel by car …

And so the last third of the book outlines strategies for reducing vehicle traffic volume: road tolls, market-priced parking, high-occupancy vehicle lanes, flex-time work schedules, provision of park-and-ride facilities, public transit service improvements, and suburban land-use planning geared to maintaining a grid rather than devolving into winding crescents and cul-de-sacs. The brief discussions of walking and cycling are insightful, even though they arise here in the context of improving motor vehicle flow.

For someone living at the far edge of greater Toronto, Road Traffic Congestion reads as a warning sign. The book illustrates how traffic congestion has spread inexorably beyond center cities to the inner suburbs, suburbs and exurbs. In the strip malls, big-box shopping centers, and curly-maze residential monocultures that are marching out from the city, we see tomorrow’s congestion in the making.

As Falcocchio and Levinson explain, adding turn lanes or a new freeway, fixes that take a few months or a few years, often just push the congestion farther down the road, while land-use policies that favour non-car travel can take a generation to be fully effective:

Although … “smart growth” land use/transportation strategies are effective (in the near term) at the neighborhood scale, significant reductions in regional VMT [vehicle mile traffic] impacts resulting from a change in land use patterns, however, takes a long time …

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